Walk down any UK pharmacy aisle and you'll see two kinds of teeth whitening: the old guard built on hydrogen peroxide, and a newer generation built on something called PAP. They both promise a whiter smile — but they get there in very different ways, and the difference is exactly where your comfort and your enamel are concerned.
Peroxide is the classic whitening active dentists use. It works — but it works by penetrating into the tooth, oxidising pigments as it goes. That penetration is what triggers the infamous whitening "zing": the peroxide reaches the nerve-rich dentine underneath and your tooth objects, loudly. It's also why the law steps in.
In the UK and EU, over-the-counter products are legally capped at just 0.1% hydrogen peroxide — a fraction of the 6% a dentist can use. Most peroxide strips sold to consumers here are, by design, too weak to do much.
PAP — phthalimidoperoxycaproic acid — is a modern whitening molecule that oxidises stain pigments on contact, at the surface where the stains actually live, without penetrating into the tooth. No penetration means no nerve irritation, which is why properly formulated PAP whitening is sensitivity-free. And because it isn't hydrogen peroxide, it isn't throttled by the 0.1% cap — PAP formulas can be strong enough to actually work.
SnowSmile strips pair PAP with coconut oil and Dead Sea minerals — up to 8 shades in 7 days, zero sensitivity, 30-day money-back guarantee.
See the PAP Whitening Strips →If you're whitening at home in the UK, the practical choice is PAP: legally strong enough to work, gentle enough to use daily, and kind to sensitive teeth — more on that in our sensitive-teeth whitening guide. Save the peroxide for the dentist's chair, if you ever need it at all.